At the Calakmul Biosphere Reserve in Campeche, Mexico, the prey spectra of sympatric jaguars ( Panthera onca ) and pumas ( Puma concolor ) were studied by examination of their scats. 10 vertebrate species were identified for jaguars and 7 for pumas, mainly mammals and some birds. Based on these diet analyses, we conclude that jaguars and pumas coexist at Calakmul by means of different food habits.